Telomeres and telomerase in Sarcoma disease and therapy.

Sarcoma is a rare tumor derived from the mesenchymal tissue and mainly found in children and adolescents. The outcome for patients with sarcoma is relatively poor compared with that for many other solid malignant tumors. Sarcomas have a highly heterogeneous pathogenesis, histopathology and biological behavior. Dysregulated signaling pathways and various gene mutations are frequently observed in sarcomas. The telomere maintenance mechanism (TMM) has recently been considered as a prognostic factor for patients with sarcomas, and alternative lengthening of telomeres (ALT) positivity has been correlated with poor outcomes in patients with several types of sarcomas. Therefore, telomeres and telomerases may be useful targets for treating sarcomas. This review aims to provide an overview of telomere and telomerase biology in sarcomas.

Large mode-field area multi-element silica glass fibers for gigahertz ultrafast lasers.

Multi-gigahertz ultrafast fiber lasers are critical for many significant applications, including bioimaging, optical communications, and laser frequency combs. The gain fiber which is expected to simultaneously satisfy large mode-field area, highly gain coefficient and resistance to photodarkening, will effectively protect mode-locked materials/devices that generally possesses low damage threshold (<10 mJ/cm2) and enhance stability in the centimeter-scale fiber lasers. However, the gain fiber still remains a significant challenge. In this study, multi-element Er-Yb: silica glass fibers with large mode-field area are fabricated. Benefiting from the multi-element design, normalized frequency V-parameter of the silica glass fiber with a core diameter of around 10 µm is <2.405. Using the large mode-field area fibers, ultrafast fiber lasers with 1.6 GHz fundamental repetition rate are proposed and demonstrated. The signal-to-noise rate of the radio-frequency signal reaching up to 90 dB and the long-term stability are realized. The results indicated the fabricated large mode-field area fibers are demonstrated to be ultrafast fiber lasers with short resonant cavities, which could be extended to other rare-earth glass fiber device for exploration of high-power amplification systems.

Interaction of ncRNAs and the PI3K/AKT/mTOR pathway: Implications for osteosarcoma.

Osteosarcoma (OS) is the most common primary malignant bone tumor in children and adolescents, and is characterized by high heterogeneity, high malignancy, easy metastasis, and poor prognosis. Recurrence, metastasis, and multidrug resistance are the main problems that limit the therapeutic effect and prognosis of OS. PI3K/AKT/mTOR signaling pathway is often abnormally activated in OS tissues and cells, which promotes the rapid development, metastasis, and drug sensitivity of OS. Emerging evidence has revealed new insights into tumorigenesis through the interaction between the PI3K/AKT/mTOR pathway and non-coding RNAs (ncRNAs). Therefore, we reviewed the interactions between the PI3K/AKT/mTOR pathway and ncRNAs and their implication in OS. These interactions have the potential to serve as cancer biomarkers and therapeutic targets in clinical applications.